检索结果-南通市图书馆

Effect of Ti and Ta content on the oxidation resistance of Co-Ni-based superalloys

International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 351-361页

作者： Yuheng Zhang Zixin Li Yunwei Gui Huadong Fu Jianxin xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

Co-Ni-based superalloys are known for their capability to function at elevated temperatures and superior hot corrosion and thermal fatigue resistance.Therefore,these alloys show potential as crucial high-temperature structural materials for aeroengine and gas turbine hot-end components.Our previous work elucidated the influence of Ti and Ta on the high-temperature mechanical properties of alloys.However,the intricate interaction among elements considerably affects the oxidation resistance of alloys.In this paper,Co-35Ni-10Al-2W-5Cr-2Mo-1Nb-xTi-(5−x)Ta alloys(x=1,2,3,4)with varying Ti and Ta contents were designed and compounded,and their oxidation resistance was investigated at the temperature range from 800 to 1000℃.After oxidation at three test conditions,namely,800℃for 200 h,900℃for 200 h,and 1000℃for 50 h,the main structure of the oxide layer of the alloy consisted of spinel,Cr_(2)O_(3),and Al_(2)O_(3)from outside to inside.Oxides consisting of Ta,W,and Mo formed below the Cr_(2)O_(3)layer.The interaction of Ti and Ta imparted the highest oxidation resistance to 3Ti2Ta alloy.Conversely,an excessive amount of Ti or Ta resulted in an adverse effect on the oxidation resistance of the alloys.This study reports the volatilization of W and Mo oxides during the oxidation process of Co-Ni-based cast superalloys with a high Al content for the first time and explains the formation mechanism of holes in the oxide layer.The results provide a basis for gaining insights into the effects of the interaction of alloying elements on the oxidation resistance of the alloys they form.

关键词： Co-Ni-based superalloys high-temperature oxidation Ti and Ta elements formation mechanism of holes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Existence of Positive Solutions to a Fractional-Kirchhoff System

引用

Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： Peng-fei Li Jun-hui xie Dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈RN\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling argument.Based on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tungsten oxide/nitrogen-doped carbon nanotubes composite catalysts for enhanced redox kinetics in lithium-sulfur batteries

引用

Chinese Journal of Chemical Engineering 2024年第3期67卷 58-67页

作者： Deqing He Zihao xie Qian Yang Wei Wang Chao Su School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-S)batteries are a significant obstacle to their widespread adoption as energy storage devices.However,recent studies have shown that tungsten oxide(WO_(3))can facilitate the conversion kinetics of polysulfides in Li-S batteries.Herein,we fabricated host materials for sulfur using nitrogen-doped carbon nanotubes(N-CNTs)and WO_(3).We used low-cost components and simple procedures to overcome the poor electrical conductivity that is a disadvantage of metal oxides.The composites of WO_(3) and N-CNTs(WO_(3)/N-CNTs)create a stable framework structure,fast ion diffusion channels,and a 3D electron transport network during electrochemical reaction processes.As a result,the WO_(3)/N-CNT-Li2S6 cathode demonstrates high initial capacity(1162 mA·h·g^(-1) at 0.5℃),excellent rate performance(618 mA·h·g^(-1) at 5.5℃),and a low capacity decay rate(0.093%up to 600 cycles at 2℃).This work presents a novel approach for preparing tungsten oxide/carbon composite catalysts that facilitate the redox kinetics of polysulfide conversion.

关键词： Li-S batteries Composites Ion diffusion channels 3D electron transport network Redox kinetics

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

引用

Journal of Iron and Steel Research(International) 2024年第3期31卷 670-687页

作者： Xian-lei Hu Qin-cheng xie Yi Yuan Ying Zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina School of Material Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential applications.However,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube method.This method involves a combination of cold rolling,annealing at a temperature of 550℃,and double rolling.The morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic characterization.The interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface properties.The results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al interface.The obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Aging-induced YTHDF aggregates impair mitochondrial function by trapping mitochondrial RNAs and suppressing their expression in the brain

引用

Protein & Cell 2024年第2期15卷 149-155页

作者： Juan Zhang Dingfeng Li Keqiang He Qiang Liu Zhongwen xie School of Life Sciences Anhui Agricultural UniversityHefei 230036China State Key Laboratory of Tea Plant Biology and Utilization School of Tea and Food Sciences and TechnologyAnhui Agricultural UniversityHefei230036China Division of Life Sciences and Medicine Hefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Department of Anesthesiology The First Affliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Anhui Province Key Laboratory of Biomedical Aging Research University of Science and Technology of ChinaHefei 230026China Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China

DearEditor,Brain aging is associated with a decrease in cognitive function,which is often accompanied by defective changes in mitochondrial morphology and reduction in mitochondrial function(Faitg et al.,2021).The main function of mitochondria is to produce energy in the form of ATP,which is vital to fulfill high energy demand of neurons,mainly for synaptic processes(Lee et al.,2018).Mitochondrial dysfunction acts as a key factor for age-related cognitive decline(Grimm and Eckert,2017).

关键词： function trapping

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A DFT study on Pt single atom loaded COF for efficient photocatalytic CO_(2)reduction

引用

Journal of Materials Science & Technology 2024年第3期170卷 87-94页

作者： Fei xie Chuanbiao Bie Jian Sun Zhenyi Zhang Bicheng Zhu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430078China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian116600China

Photocatalytic CO_(2)reduction provides a promising strategy for the alleviation of greenhouse effect and energy shortage problem.Metal single atom modification is an effective method to improve the CO_(2)reduction performance of covalent organic framework(COF)photocatalysts,while the intrinsic mechanism is not revealed in depth.Herein,a Pt-COF photocatalytic system was constructed by embedding Pt single atom in TFPT-TMT-COF(TFPT:1,3,5-tris(4-formylphenyl)-triazine,TMT:2,4,6-trimethyl-1,3,5-triazine).Based on density functional theory(DFT)calculation,the geometric structure and electronic property of Pt-COF were investigated,and the CO_(2)adsorption and reduction reaction process on Pt-COF were simulated.The results show that the Pt atom can be steadily anchored in COF via the formation of Pt-N and Pt-C bonds.Moreover,there is strong electronic interaction between Pt and COF.The incorporation of Pt atom benefits the CO_(2)reduction activity of COF from multiple aspects:(ⅰ)reducing the band gap and improving light absorption;(ⅱ)enhancing CO_(2)adsorption and activating the CO_(2)molecule;(ⅲ)decreasing the energy barrier in the hydrogenation step of CO_(2)→COOH,thus facilitating CO_(2)conversion to CO;(ⅳ)inhibiting the hydrogenation of CO,thereby increasing the selectivity of CO.This work brings a novel insight into the excellent CO_(2)reduction performance of Pt modified COF,and provides useful references for the design of single atom photocatalysts.

关键词： Photocatalysis Carbon dioxide reduction Covalent organic framework Pt single atom Theoretical calculation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Metallogenesis of the Baidi Au-Sb deposit, southwest Guizhou Province, China: mineralogical and geochemical evidence from sulfur-bearing minerals

引用

Acta Geochimica 2024年第2期43卷 199-213页

作者： Jun Yan Yong Xia Qinping Tan Zhuojun xie Guosong Ji State KeyLaboratory of Ore Deposit Geochemistry Institute of GeochemistryChineseAcademy of SciencesGuiyang 550081China Guizhou InstituteofTechnology Guiyang550003China No.102 GeologicalTeam Guizhou Bureau of Geologyand Mineral Exploration&DevelopmentZunyi563003China

The Baidi Au-Sb deposit, which contains 8 t of Au and 10,979 Mt of Sb, is a typical and rare paragenetic deposit located in southwestern Guizhou Province, China.Previous studies have focused on individual ores, but have not combined them to identify their paragenetic mechanism or metallogenic regularity. Therefore, we used field investigations, microscopic observations, and in situ analyses to identify the spatial distribution, mineral paragenesis, compositional evolution, and metallogenic material sources of the ore bodies. We also determined the Au and Sb paragenetic characteristics and the metallogenesis of the deposit. The main Au-bearing minerals in the deposit were early(Apy1–2) and late(Apy3) stage arsenopyrites, as well as pre-mineralization(Py1), mineralization(Py2–5), and late mineralization(Py6–7) stage pyrites. The main Sb-bearing minerals were stibnite(Snt), skinnerite, bournonite,and valentinite. The minerals formed in the order of Py1,Py2–3 + Apy1, Py4–5 + Apy2, Snt, and Py6–7 + Apy3.The δ34S values of the arsenopyrites and pyrites ranged from-5 to 5‰, while those of stibnite were mostly less than-5‰ in the later mineralization stages. Sulfur was provided by deep magmatic hydrothermal fluids, but sedimentary sulfur was added in the later stages. Moreover,the trace elemental contents fluctuated and eventually became similar to those of the sedimentary strata. By comprehensively considering the ores along with the geological characteristics of the deposit, we determined that deep magma provided the Au during ore formation. Later tectonic changes provided Sb from the sedimentary strata,which precipitated along fault expansion areas and produced Au and Sb paragenesis.

关键词： Au-Sb mineralization Arsenopyrite Pyrite Stibnite Metallogenetic process

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Adaptive Event-Triggered Time-Varying Output Group Formation Containment Control of Heterogeneous Multiagent Systems

引用

IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1398-1409页

作者： Lihong Feng Bonan Huang Jiayue Sun Qiuye Sun Xiangpeng xie College of Information Science and Engineering Northeastern UniversityShenyang 110819China College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China IEEE

In this paper,a class of time-varying output group formation containment control problem of general linear hetero-geneous multiagent systems(MASs)is investigated under directed topology.The MAS is composed of a number of tracking leaders,formation leaders and followers,where two different types of leaders are used to provide reference trajectories for movement and to achieve certain formations,respectively.Firstly,compen-sators are designed whose states are estimations of tracking lead-ers,based on which,a controller is developed for each formation leader to accomplish the expected formation.Secondly,two event-triggered compensators are proposed for each follower to evalu-ate the state and formation information of the formation leaders in the same group,respectively.Subsequently,a control protocol is designed for each follower,utilizing the output information,to guide the output towards the convex hull generated by the forma-tion leaders within the group.Next,the triggering sequence in this paper is decomposed into two sequences,and the inter-event intervals of these two triggering conditions are provided to rule out the Zeno behavior.Finally,a numerical simulation is intro-duced to confirm the validity of the proposed results.

关键词： Adaptive control event-triggered mechanisms for-mation containment(FC) heterogeneous multiagent systems time-varying group formation.

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

High corrosion and wear resistant electroless Ni–P gradient coatings on aviation aluminum alloy parts

引用

International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 155-164页

作者： Bo Wang Jiawei Li Zhihui xie Gengjie Wang Gang Yu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410012China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province/College of Chemistry and Chemical Engineering China West Normal UniversityNanchong 637002China Zhongchuan Machinery Ltd.Co. Aero Engine Corporation of ChinaChangsha 410200China

A Ni–P alloy gradient coating consisting of multiple electroless Ni–P layers with various phosphorus contents was prepared on the aviation aluminum alloy. Several characterization and electrochemical techniques were used to characterize the different Ni–P coatings’ morphologies, phase structures, elemental compositions, and corrosion protection. The gradient coating showed good adhesion and high corrosion and wear resistance, enabling the application of aluminum alloy in harsh environments. The results showed that the double zinc immersion was vital in obtaining excellent adhesion (81.2 N). The optimal coating was not peeled and shredded even after bending tests with angles higher than 90°and was not corroded visually after 500 h of neutral salt spray test at 35℃. The high corrosion resistance was attributed to the misaligning of these micro defects in the three different nickel alloy layers and the amorphous structure of the high P content in the outer layer. These findings guide the exploration of functional gradient coatings that meet the high application requirement of aluminum alloy parts in complicated and harsh aviation environments.

关键词： aluminum alloy electroless nickel coating corrosion adhesion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Innovation of Evaluation and Design of Vehicle Acceleration Sound Based on EEG Signals

引用

Journal of Bionic Engineering 2024年第1期21卷 344-361页

作者： Liping xie XinYou Lin Wan Chen Zhien Liu Yawei Zhu College of Mechanical Engineering&Automation Fuzhou UniversityFuzhou 350108China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China

There is a bottleneck in the design of vehicle sound that the subjective perception of sound quality that combines multiple psychological factors fails to be accurately and objectively quantified.Therefore,EEG signals are introduced in this paper to investigate the evaluation and design method of vehicle acceleration sound with powerful sound quality.Firstly,the experiment of EEG acquisition and subjective evaluation under the stimulation of powerful vehicle sounds is conducted,respectively,then three physiological EEG features of PSD_β,PSD_γand DE are constructed to evaluate the vehicle sounds based on the correlation analysis algorithms.Subsequently,the Adaptive Genetic Algorithm(AGA)is proposed to optimize the Elman model,where an intelligent model(AGA–Elman)is constructed to objectively predicate the perception of subjects for the vehicle sounds with powerful sound quality.The results demonstrate that the error of the constructed AGA–Elman model is only 2.88%,which outperforms than the traditional BP and Elman model;Finally,two vehicle acceleration sounds(Design1 and Design2)are designed based on the constructed AGA–Elman model from the perspective of order modulation and frequency modulation,which provide the acoustic theoretical guidance for the design of vehicle sound incorporating the EEG signals.

关键词： EEG signal Brain activity analysis Vehicle sound design Adaptive genetic algorithm-Elman model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：